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Diagnosis and Treatment of Normal-Pressure Hydrocephalus Syndrome—an Update

A special issue of Journal of Clinical Medicine (ISSN 2077-0383). This special issue belongs to the section "Clinical Neurology".

Deadline for manuscript submissions: closed (1 July 2022) | Viewed by 47000

Special Issue Editors


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Guest Editor
Department of Neurosurgery and Neurotraumatology and Neurosurgery Research Unit (UNINN), Vall d’Hebron University Hospital, Universitat Autònoma de Barcelona, Passeig Vall d’Hebron 119–129, 08035 Barcelona, Spain
Interests: cerebrospinal fluid dynamics; normotensive hydrocephalus; traumatic brain injuries (TBI); pediatric neurosurgery; skull base surgery; surgery of the cranio-cervical junction
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Guest Editor
Vall d'Hebron Institut de Recerca, Barcelona, Spain
Interests: traumatic brain injury; intracranial pressure
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Since the original description of normal-pressure hydrocephalus (NPH) syndrome by Hakim in 1964, there have been significant advancements in awareness among neurologists and neurosurgeons of NPH, as it is one of the few causes of reversible cognitive deteriorarion in the elderly population. The apparent increase in the prevalence of this disease is due, in part, to the growth in the number of older persons in developed countries. In addition, a better physiopathological understanding of this syndrome, the availability of better biomarkers of the disease, and better and more precise hardware for cerebrospinal fluid (CSF) shunting has reduced the morbidity of NPH-ameliorating surgery and improved the final outcome of these fragile patients. In patients with potential NPH syndrome, adequate screening and correct diagnosis are the first necessary steps, though the different available guidelines are somewhat contradictory in this regard. Once the diagnosis is done, the need to choose adequate hardware for shunting is the most important dilemma that the neurosurgeon faces, particularly since there are few evidence-based studies that show the superiority of any specific type of valve. However, the heterogeneous results of surgery reported in the literature in the last 25 years and the differences in the figures of significant post-surgical morbidity have raised some concerns, and even skepticism, among neurologists and neurosurgeons about the value of surgical treatment in these patients.

The goal of this Special Issue is to review controversial aspects regarding the screening methods, diagnostic tests, and treatment of patients with NPH that are relevant to individualizing treatment and improving outcomes after surgery. In addition, we review the different types of available hardware and discuss the advantages and disadvantages of the most frequently-used devices. We remark on the need for the neurosurgeon to be aware of the differences among commercially-available devices and to avoid the common mistake of choosing a one-size-fits-all system for this group of patients. The variables to take into account for selecting the most appropiate CSF device are discussed. Careful selection can reduce the risk of what has been named “shunt–patient mismatch”, which is the most important cause of increased surgical risks after surgery. With a more rational approach to shunting, we believe that we can increase the chances of a positive outcome and increase the quality of life of aged patients with this syndrome.

Prof. Dr. Maria A. Poca
Prof. Dr. Juan Sahuquillo
Guest Editors

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Keywords

  • hydrocephalus
  • normal pressure hydrocephalus
  • adult chronic hydrocephalus
  • Hakim and Adams’ syndrome
  • CSF dynamic studies
  • intracranial pressure monitoring
  • shunt selection
  • congenital hydrocephalus
  • shunt overdrainage
  • shunt–patient mismatch
  • Hakim's Syndrome
  • ventriculo-peritoneal shunts
  • cerebrospinal fluid shunts

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Published Papers (10 papers)

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Editorial

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5 pages, 223 KiB  
Editorial
To Shunt or Not to Shunt Patients with Idiopathic Normal Pressure Hydrocephalus? A Reappraisal of an Old Question
by Juan Sahuquillo and Maria A. Poca
J. Clin. Med. 2020, 9(12), 4120; https://doi.org/10.3390/jcm9124120 - 21 Dec 2020
Cited by 4 | Viewed by 3125
Abstract
The possibility that the cerebral ventricles can dilate without any increase in the pressure of the cerebrospinal fluid (CSF) was recognized in 1935 by Penfield who reported a patient in whom “…the cerebrospinal fluid spaces are closed and the ventricles progressively enlarge without [...] Read more.
The possibility that the cerebral ventricles can dilate without any increase in the pressure of the cerebrospinal fluid (CSF) was recognized in 1935 by Penfield who reported a patient in whom “…the cerebrospinal fluid spaces are closed and the ventricles progressively enlarge without the measured intraventricular pressure rising above 150 to 200 mm of water” [...] Full article

Research

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13 pages, 1278 KiB  
Article
Thyroid Hormones and Health-Related Quality of Life in Normal Pressure Hydrocephalus Patients before and after the Ventriculoperitoneal Shunt Surgery: A Longitudinal Study
by Mindaugas Urbonas, Nijole Raskauskiene, Vytenis Pranas Deltuva and Adomas Bunevicius
J. Clin. Med. 2022, 11(15), 4438; https://doi.org/10.3390/jcm11154438 - 30 Jul 2022
Cited by 1 | Viewed by 1548
Abstract
Objective: The aim of this study was to explore the serum levels of thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3), and to correlate the hormone levels among iNPH patients with their self-reported quality of life before and three months after [...] Read more.
Objective: The aim of this study was to explore the serum levels of thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3), and to correlate the hormone levels among iNPH patients with their self-reported quality of life before and three months after the surgery. Methods: Twenty-five patients (52% women), mean age 63.5 (SD 9.5) years, were operated on by inserting a VP shunt. Patients with FT3 level ≤3.34 pmol/L were diagnosed as having low T3 syndrome. Results: The changes in thyroid hormones resulted in a U-shaped curve throughout the follow-up period. The significant changes occurred the next day after the surgery, including a decrease in TSH, FT3, and an increase in FT4. Additionally, the decrease occurred in mean FT3 for six patients with preoperative low T3 syndrome. Three months after the surgery, thyroid hormones were restored to their baseline and/or normal values. All six patients with preoperative low T3 syndrome had significant improvement in all SF-36 subscales (except for the role emotional and physical). Patients with preoperative normal high FT3 and low FT4 had increased FT3/FT4 ratio which was associated with deterioration in all SF-36 subscales 3 months after the surgery. Conclusion: Routine assessment of the FT3/FT4 ratio might be a simple and effective tool for the risk stratification of iNPH patients before VP shunt surgery. Full article
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12 pages, 1330 KiB  
Article
Callosal Angle Sub-Score of the Radscale in Patients with Idiopathic Normal Pressure Hydrocephalus Is Associated with Positive Tap Test Response
by Efstratios-Stylianos Pyrgelis, George P. Paraskevas, Vasilios C. Constantinides, Fotini Boufidou, Georgios Velonakis, Leonidas Stefanis and Elisabeth Kapaki
J. Clin. Med. 2022, 11(10), 2898; https://doi.org/10.3390/jcm11102898 - 20 May 2022
Cited by 6 | Viewed by 2967
Abstract
The aim of the present study was the implementation of the composite imaging “Radscale” in patients with idiopathic normal pressure hydrocephalus (iNPH) and the evaluation of its score, as well as absolute stroke volume and peak flow velocity of cerebrospinal fluid (CSF) in [...] Read more.
The aim of the present study was the implementation of the composite imaging “Radscale” in patients with idiopathic normal pressure hydrocephalus (iNPH) and the evaluation of its score, as well as absolute stroke volume and peak flow velocity of cerebrospinal fluid (CSF) in aqueduct as indicators of a positive response following a tap test. Forty-five patients with iNPH were included. Clinical evaluation involved the 10 m timed walk test before and every 24 h for 3 consecutive days after evacuative lumbar puncture (LP). Neuropsychological evaluation comprised a mini mental state examination (MMSE), frontal assessment battery (FAB), 5-word test (5WT) and CLOX drawing test 1 and 2, which were carried out before and 48 h after LP. The tap test’s response was defined as a ≥20% improvement in gait and/or a ≥10% improvement in neuropsychological tests. All scores of neuropsychological and clinical variables, except for immediate 5WT and CLOX-1, differed significantly before and 48 h after LP. Improvement in time and steps of a 10 m timed walk test differed significantly between female and male patients. Out of 45 total patients, 19 were tap test responders and 26 non-responders. The total score of Radscale and CSF flow parameters did not differ between responders and non-responders. However, “Callosal angle” sub-score differed significantly between these two groups. A greater “callosal angle” sub-score, meaning more acute callosal angle, was associated with a positive tap test response, rendering it a useful measurement in the stratification of iNPH patients that will potentially respond to CSF shunting. Full article
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10 pages, 552 KiB  
Article
Clinical Outcomes of Shunting in Normal Pressure Hydrocephalus: A Multicenter Prospective Observational Study
by Sokol Trungu, Antonio Scollato, Luca Ricciardi, Stefano Forcato, Filippo Maria Polli, Massimo Miscusi and Antonino Raco
J. Clin. Med. 2022, 11(5), 1286; https://doi.org/10.3390/jcm11051286 - 26 Feb 2022
Cited by 5 | Viewed by 5234
Abstract
Background: Normal pressure hydrocephalus (NPH) is characterized by the triad of dementia, gait disturbance and urinary incontinence, all potentially reversible following a ventriculoperitoneal shunt (VPS). This study aims to evaluate the clinical outcomes of shunting in normal pressure hydrocephalus following a new [...] Read more.
Background: Normal pressure hydrocephalus (NPH) is characterized by the triad of dementia, gait disturbance and urinary incontinence, all potentially reversible following a ventriculoperitoneal shunt (VPS). This study aims to evaluate the clinical outcomes of shunting in normal pressure hydrocephalus following a new standardized protocol. Methods: This study is designed according to the STROBE guidelines. Demographical, clinical, surgical and radiological data were collected from May 2015 to November 2019. Gait, balance and incontinence data based on the NPH European scale were collected before and after one, six and twelve months of treatment with a VPS. Clinical symptoms and changes of the stoke volume, measured on phase-contrast MRI, were used to evaluate improvement after VPS surgery. Results: One hundred and eighty-one consecutive patients met the inclusion criteria. The mean age was 73.1 years (59–86) and mean follow-up was 38.3 months (13–50). The gait (58.5 ± 14.3 to 70.1 ± 13.4, p < 0.001), the balance (66.7 ± 21.5 to 71.7 ± 22.1, p = 0.001), continence domain (69.9 ± 20.5 to 76 ± 20, p = 0.002) scores and neuropsychological scales showed a statistically significant improvement over the follow-up. The overall improvement after 12 months was present in 91.2% of patients. An overall complication rate of 8.8% and a reoperation rate of 9.4% were recorded, respectively. Conclusions: Surgical treatment by VPS for NPH improves symptoms in most patients, when accurately selected. A standardized protocol and a multidisciplinary team dedicated to this disorder is needed to achieve an early and correct diagnosis of NPH. Follow-up with stroke volume measurement is a valuable tool for the early diagnosis of shunt malfunction or the need for valve adjustment. Full article
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10 pages, 605 KiB  
Article
Elevated CSF LRG and Decreased Alzheimer’s Disease Biomarkers in Idiopathic Normal Pressure Hydrocephalus
by Aleksi Vanninen, Madoka Nakajima, Masakazu Miyajima, Tuomas Rauramaa, Merja Kokki, Tadeusz Musialowicz, Petra M. Mäkinen, Sanna-Kaisa Herukka, Anne M. Koivisto, Juha E. Jääskeläinen, Mikko Hiltunen and Ville Leinonen
J. Clin. Med. 2021, 10(5), 1105; https://doi.org/10.3390/jcm10051105 - 6 Mar 2021
Cited by 17 | Viewed by 2624
Abstract
Leucine-rich-alpha-2-glykoprotein (LRG) is suggested as a potential biomarker for idiopathic normal pressure hydrocephalus (iNPH). Our goal was to compare the cerebrospinal fluid (CSF) LRG levels between 119 iNPH patients and 33 age-matched controls and with the shunt responses and the brain biopsy Alzheimer’s [...] Read more.
Leucine-rich-alpha-2-glykoprotein (LRG) is suggested as a potential biomarker for idiopathic normal pressure hydrocephalus (iNPH). Our goal was to compare the cerebrospinal fluid (CSF) LRG levels between 119 iNPH patients and 33 age-matched controls and with the shunt responses and the brain biopsy Alzheimer’s disease (AD) pathology among the iNPH patients. CSF LRG, Aβ1-42, P-tau181, and T-tau were measured by using commercial ELISAs. The LRG levels in the CSF were significantly increased in the iNPH patients (p < 0.001) as compared to the controls, regardless of the AD pathology. However, CSF LRG did not correlate with the shunt response in contrast to the previous findings. The CSF AD biomarkers, i.e., Aβ1-42, T-tau, and P-tau correlated with the brain biopsy AD pathology as expected but were systematically lower in the iNPH patients when compared to the controls (<0.001). Our findings support that the LRG levels in the CSF are potentially useful for the diagnostics of iNPH, independent of the brain AD pathology, but contrary to previous findings, not for predicting the shunt response. Our findings also suggest a need for specific reference values of the CSF AD biomarkers for the diagnostics of comorbid AD pathology in the iNPH patients. Full article
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Review

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21 pages, 5729 KiB  
Review
Shunt Overdrainage: Reappraisal of the Syndrome and Proposal for an Integrative Model
by Bienvenido Ros, Sara Iglesias, Jorge Linares, Laura Cerro, Julia Casado and Miguel Angel Arráez
J. Clin. Med. 2021, 10(16), 3620; https://doi.org/10.3390/jcm10163620 - 17 Aug 2021
Cited by 16 | Viewed by 9327
Abstract
Although shunt overdrainage is a well-known complication in hydrocephalus management, the problem has been underestimated. Current literature suggests that the topic requires more examination. An insight into this condition is limited by a lack of universally agreed-upon diagnostic criteria, heterogeneity of published series, [...] Read more.
Although shunt overdrainage is a well-known complication in hydrocephalus management, the problem has been underestimated. Current literature suggests that the topic requires more examination. An insight into this condition is limited by a lack of universally agreed-upon diagnostic criteria, heterogeneity of published series, the multitude of different management options and misunderstanding of relationships among pathophysiological mechanisms involved. We carried out a review of the literature on clinical, radiological, intracranial pressure (ICP), pathophysiological and treatment concepts to finally propose an integrative model. Active prophylaxis and management are proposed according to this model based on determination of pathophysiological mechanisms and predisposing factors behind each individual case. As pathophysiology is progressively multifactorial, prevention of siphoning with gravitational valves or antisiphon devices is mandatory to avoid or minimize further complications. Shunt optimization or transferal and neuroendoscopy may be recommended when ventricular collapse and cerebrospinal fluid isolation appear. Cranial expansion may be useful in congenital or acquired craniocerebral disproportion and shunting the subarachnoid space in communicating venous hydrocephalus and idiopathic intracranial hypertension. Full article
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17 pages, 18313 KiB  
Review
Reappraisal of Pediatric Normal-Pressure Hydrocephalus
by Owen P. Leary, Konstantina A. Svokos and Petra M. Klinge
J. Clin. Med. 2021, 10(9), 2026; https://doi.org/10.3390/jcm10092026 - 9 May 2021
Cited by 1 | Viewed by 4423
Abstract
While normal-pressure hydrocephalus (NPH) is most commonly diagnosed in older adulthood, a significant body of literature has accumulated over half a century documenting the clinical phenomenon of an NPH-like syndrome in pediatric patients. As in adult NPH, it is likely that pediatric NPH [...] Read more.
While normal-pressure hydrocephalus (NPH) is most commonly diagnosed in older adulthood, a significant body of literature has accumulated over half a century documenting the clinical phenomenon of an NPH-like syndrome in pediatric patients. As in adult NPH, it is likely that pediatric NPH occurs due to a heterogeneous array of developmental, structural, and neurodegenerative pathologies, ultimately resulting in aberrant cerebrospinal fluid (CSF) flow and distribution within and around the brain. In this review, we aimed to systematically survey the existing clinical evidence supporting the existence of a pediatric form of NPH, dating back to the original recognition of NPH as a clinically significant subtype of communicating hydrocephalus. Leveraging emergent trends from the old and more recent published literature, we then present a modern characterization of pediatric NPH as a disorder firmly within the same disease spectrum as adult NPH, likely with overlapping etiology and pathophysiological mechanisms. Exemplary cases consistent with the diagnosis of pediatric NPH selected from the senior author’s neurosurgical practice are then presented alongside the systematic review to aid in discussion of the typical clinical and radiographic manifestations of pediatric NPH. Common co-morbidities and modern surgical treatment options are also described. Full article
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29 pages, 10987 KiB  
Review
CSF Dynamics for Shunt Prognostication and Revision in Normal Pressure Hydrocephalus
by Afroditi Despina Lalou, Marek Czosnyka, Michal M. Placek, Peter Smielewski, Eva Nabbanja and Zofia Czosnyka
J. Clin. Med. 2021, 10(8), 1711; https://doi.org/10.3390/jcm10081711 - 15 Apr 2021
Cited by 11 | Viewed by 3890
Abstract
Background: Despite the quantitative information derived from testing of the CSF circulation, there is still no consensus on what the best approach could be in defining criteria for shunting and predicting response to CSF diversion in normal pressure hydrocephalus (NPH). Objective: We aimed [...] Read more.
Background: Despite the quantitative information derived from testing of the CSF circulation, there is still no consensus on what the best approach could be in defining criteria for shunting and predicting response to CSF diversion in normal pressure hydrocephalus (NPH). Objective: We aimed to review the lessons learned from assessment of CSF dynamics in our center and summarize our findings to date. We have focused on reporting the objective perspective of CSF dynamics testing, without further inferences to individual patient management. Discussion: No single parameter from the CSF infusion study has so far been able to serve as an unquestionable outcome predictor. Resistance to CSF outflow (Rout) is an important biological marker of CSF circulation. It should not, however, be used as a single predictor for improvement after shunting. Testing of CSF dynamics provides information on hydrodynamic properties of the cerebrospinal compartment: the system which is being modified by a shunt. Our experience of nearly 30 years of studying CSF dynamics in patients requiring shunting and/or shunt revision, combined with all the recent progress made in producing evidence on the clinical utility of CSF dynamics, has led to reconsidering the relationship between CSF circulation testing and clinical improvement. Conclusions: Despite many open questions and limitations, testing of CSF dynamics provides unique perspectives for the clinician. We have found value in understanding shunt function and potentially shunt response through shunt testing in vivo. In the absence of infusion tests, further methods that provide a clear description of the pre and post-shunting CSF circulation, and potentially cerebral blood flow, should be developed and adapted to the bed-space. Full article
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18 pages, 3442 KiB  
Review
How to Choose a Shunt for Patients with Normal Pressure Hydrocephalus: A Short Guide to Selecting the Best Shunt Assembly
by Juan Sahuquillo, Katiuska Rosas, Helena Calvo, Aloma Alcina, Dario Gándara, Diego López-Bermeo and Maria-Antonia Poca
J. Clin. Med. 2021, 10(6), 1210; https://doi.org/10.3390/jcm10061210 - 15 Mar 2021
Cited by 3 | Viewed by 7497
Abstract
Most patients with hydrocephalus are still managed with the implantation of a cerebrospinal fluid (CSF) shunt in which the CSF flow is regulated by a differential-pressure valve (DPV). Our aim in this review is to discuss some basic concepts in fluid mechanics that [...] Read more.
Most patients with hydrocephalus are still managed with the implantation of a cerebrospinal fluid (CSF) shunt in which the CSF flow is regulated by a differential-pressure valve (DPV). Our aim in this review is to discuss some basic concepts in fluid mechanics that are frequently ignored but that should be understood by neurosurgeons to enable them to choose the most adequate shunt for each patient. We will present data, some of which is not provided by manufacturers, which may help neurosurgeons in selecting the most appropriate shunt. To do so, we focused on the management of patients with idiopathic “normal-pressure hydrocephalus” (iNPH), as one of the most challenging scenarios, in which the combination of optimal technology, patient characteristics, and knowledge of fluid mechanics can significantly modify the surgical results. For a better understanding of the available hardware and its evolution over time, we will have a second look at the design of the first DPV and the reasons why additional devices were incorporated to control for shunt overdrainage and its related complications. We try to persuade the reader that a clear understanding of the physical concepts of the CSF and shunt dynamics is key to understand the pathophysiology of iNPH and to improve its treatment. Full article
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14 pages, 1898 KiB  
Review
Considerations in the Use of Gravitational Valves in the Management of Hydrocephalus. Some Lessons Learned with the Dual-Switch Valve
by Maria A. Poca, Dario F. Gándara, Katiuska Rosas, Aloma Alcina, Diego López-Bermeo and Juan Sahuquillo
J. Clin. Med. 2021, 10(2), 246; https://doi.org/10.3390/jcm10020246 - 12 Jan 2021
Cited by 5 | Viewed by 3395
Abstract
In the past decade, there has been a clear trend towards better outcomes in patients with hydrocephalus, especially those with normal pressure hydrocephalus (NPH). This is partly due to the availability of more sophisticated hardware and a better understanding of implants. However, there [...] Read more.
In the past decade, there has been a clear trend towards better outcomes in patients with hydrocephalus, especially those with normal pressure hydrocephalus (NPH). This is partly due to the availability of more sophisticated hardware and a better understanding of implants. However, there is little evidence to show the superiority of a specific type of valve over another. The most commonly reported consequence of hydrodynamic mismatch is shunt over-drainage. Simple differential pressure valves, with a fixed opening pressure or even adjustable valves, lead to non-physiologic intraventricular pressure (IVP) as soon as the patient moves into an upright posture. These valves fail to maintain IVP within physiological limits due to the changes in hydrostatic pressure in the drainage system. To solve this problem more complex third-generation hydrostatic valves have been designed. These gravitational devices aim to reduce flow through a shunt system when the patient is upright but there are important technical differences between them. Here we review the main characteristics of the Miethke® Dual-Switch valve, which includes two valve chambers arranged in parallel: a low-opening pressure valve, designed for working in the supine position, and a second high-opening pressure valve, which starts working when the patient assumes the upright position. This paper specifies the main advantages and drawbacks of this device and provide a series of recommendations for its use. The discussion of this specific gravitational valve allows us to emphasize the importance of using gravitational control in implanted shunts and some the caveats neurosurgeons should take into consideration when using gravitational devices in patients with hydrocephalus. The correct function of any gravitational device depends on adequate device implantation along the vertical body axis. Misalignment from the vertical axis equal to or more than 45° might eliminate the beneficial effect of these devices. Full article
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